how to display only one record

ginginca

<?php	  // Query the Database
$query = mysql_query("SELECT * FROM userid"); name

while($row = mysql_fetch_array($query)) { 
   echo "emailaddress: " . $row["emailaddress"] . "<br>"; 
} ?>

This is displaying all email addresses in the database. How would I display only the one from the session? (The one for the logged-in user).

Thank you in advance.

Piranha

You need a where-statement in your SQL question, something like the following:

SELECT * FROM userid WHERE userid = $user

To be sure that you get only one result you can use limit as well, like this:

SELECT * FROM userid WHERE userid = $user LIMIT 0, 1

ginginca

(userid is my table)

How does it query the correct user information once they are logged in?

ClarkF1

You could save the userid in a session variable which gets by each page and use it in subsequent queries.

As for the original sql query........don't use * if you don't need all the information.

If you just need the email address use:

SELECT emailaddress FROM userid WHERE userid = $user LIMIT 1

(LIMIT 1 does the same as LIMIT 0,1)

If you have a large database, this will speed up the query as it's only retrieving one piece of information from the database.

ginginca

Re: don't use * if you don't need all the information

I will need all the fields in this table. (Not all the records). So take this out?

Re: WHERE userid = $user

userid is my table (not a field). I am confused by this comment.

Piranha

You need some kind of pointer to know what rows the database should return. Since I have no idea what fields you have and used userid since it looks like a primary key. It seems like you need to read up a bit about how to use it. Please look at the link below:

http://www.w3schools.com/sql/sql_where.asp

ginginca

I got it figured out.

Thanks.

ClarkF1

ginginca wrote:
Re: don't use * if you don't need all the information

I will need all the fields in this table. (Not all the records). So take this out?

Re: WHERE userid = $user

userid is my table (not a field). I am confused by this comment.

I used userid as an example of a field as I don't know the structure of your database.

When constructing a query, only retrieve the information from the database that you will actually be using. You can use subsequent queries for retrieving other data later on if required.......e.g. if you only need the emailaddress of a user don't query the whole row of the database for that user using *

It helps database load and optimise query times